— In this paper, the design of a highly efficient and flexibly deployable wireless backhaul is addressed as a promising alternative to the typical wired solutions. To this end, a novel approach for relay transmissions with multiple antennas is proposed in the framework of wireless meshed backhaul system design optimization. The link and system level performance are assessed and different mesh topologies and relaying protocols are investigated. The optimality of the approach relies on the reconfigurable /adaptive use of the degrees of freedom offered by the combination of multiple antennas and relays and is promising for both wireless backhaul and access applications.